Great! Thank you very much!

Works great.

Almost perfect, but feedburner feeds won't work with this addon.

Works well but in the bottom of RSS page it creates such a garbage:

document.onselectstart = function () {return true; };document.oncontextmenu = function () { return true; }; document.onmousedown = function () { return true; }; document.onkeydown = function () { return true; }; document.body.onselectstart = function () {return true; };document.body.oncontextmenu = function () { return true; }; document.body.onmousedown = function () { return true; }; document.body.onkeydown = function () { return true; }; jQuery(document).unbind("keydown");jQuery(document).unbind("mousedown");

Works well.

I don't understand why Mozilla would remove this function, but thanks to Aurelien David we have it back! It works as well as when it was built in.